Height adjusting devices for chairs, tables, and the like



Nov. 15, 1966 1.. R. ELFSTROM HEIGHT ADJUSTING DEVICES FOR CHAIRSTABLES, AND THE LIKE Filed July 26, 1965 INVENTOR LA R5 RICHARD ELFSTROMATTORNEYS United States Patent 3,285,656 HEIGHT ADJUSTING DEVICES FORCHAIRS, TABLES, AND THE LIKE Lars R. Elfstrom, Goteborg, Sweden,assignor to System Communica Aktiebolag, Goteborg, Sweden Filed July 26,1965, Ser. No. 474,841 2 Claims. (Cl. 297-337) The present inventionrelates to a height adjusting device for chairs, tables, and the like,of the type where the seat or table top, respectively, is disposed onthe end of a tube, the lower and straight "end-portion of which slidesonto or into, in the latter case, a sleeve-shaped, vertical column fixedon an under-frame.

The object of the invention is to create a simple height adjustingdevice inexpensive to produce, convenient to handle and attractive bothfrom the point of view of appearance and cleaning.

The invention is substantially characterised by the supporting tubebeing provided with a number of displaceable bodies, preferably balls,the lowermost of which is carried by the column, there being a blockingmember, capable of being introduced between two adjacent displaceablebodies through an opening in the tube, and disposed at a requisitedistance from the upper end of the column.

In the case of chairs, tables and the like, where the seat or table topand the like can be raised like a flap from its position of use, theblocking member can, according to the invention, consist of a pin fixedto the underside of the seat or table top.

The accompanying drawing illustrates an embodiment of the invention, andin the said drawings:

FIGURE 1 represents a side elevation of a chair provided with a heightadjusting device according to the invention, and also partially asection through the said device;

FIGURE 2 shows a vertical cross section through one of the detailsaccording to a somewhat modified design; and

FIGURE 3 is a horizontal cross section through the chair along the lineIII-III in FIGURE 1.

The numeral 1 in the drawing denotes a chair underframe of conventionaldesign. From this frame rises a vertical column 2. A compression spring3 is disposed on the upper end of the column. The lower, straightendportion of a tube 4 is slidably fitted to the column 2 as a part ofthe said tube, which then curves off and continues upwards at such anangle that balls 5 disposed inside the tube fall by gravitation on tothe lowest ball held in position by the column 2, interacting with thespring 3. After a further bend, the tube 4 continues upwards at a moreacute inclination while successively being flattened, the top end ofsame being fitted with a slidably rotatable adjusting arrangement 6 of aback rest 7. At the upwardturned side of the tubular portion between thetwo bends, two supporting brackets 9 for a seat 8 are fitted, andbetween them is a plate 10 fixed to the underside of the seat. The saidplate 10 is provided with a projection acting as a blocking member e.g.a pin 11 which, when the seat is set in position of use by being hingedon the pivot 13, is made to enter between two adjacent balls 5 throughan opening 12 provided in the tube 4.

Upon raising the seat into vertical position, the blocking member 11 iswithdrawn from the tube 4, allowing same to be adjusted to requiredheight. The balls are then 3,285,656 Patented Nov. 15, 1966 moved ineither one or the other direction in relation to the tube. Aftercompleted adjustment, the seat is restored to horizontal position, andthe blocking member 11 then pushes its way through between two adjacentballs disposed at a requisite distance from the upper end of the columnand which happen to be positioned at the opening 12 (according to theamount of height adjustment), with the result that the balls disposedbetween the blocking member 11 and the column 2 transmit the load to thecolumn on the underframe.

The embodiment shown in FIGURE 2 diifers from that described above onlyby the frame-supported column being made in the form of a sleeve 14 intowhich the lower, straight end-portion of the tube 4 is capable of beingtelescoped.

The invention is not limited to the embodiments described above andshown in the drawing as these may vary in different ways withoutdeviating from the fundamental idea of the invention, according to theappended claims.

What I claim is:

1. Height adjustable furniture support comprising a column, means forvertically supporting said column on a horizontal surface when in use, atube telescopically connected at one end to said column, a springmounted on said column, a series of balls freely moveable andindividually rotatable in said tube with adjacent balls bearing againstone another and having one of said balls bearing against said spring,said tube having a side opening, a support pivotally mounted on saidtube, and a blocking member carried by said support for being insertedat times through said tube side opening and between an adjacent pair ofsaid balls when said support is in its load supporting position.

2. Height adjustably furniture support as claimed in claim 1 whereinsaid tube telescopically connected end is straight and positioned inline with said column, said tube further has a portion extending on anangle from said straight end portion and away from said columnpermitting said balls to roll under gravity towards said column when inuse, said support has one edge hingedly connected to said tube angularportion and said tube slot is positioned on a side of said tube angularportion.

References Cited by the Examiner UNITED STATES PATENTS 580,665 4/ 1897Goshorn 248-162 1,711,526 5/1929 Forsyth 297-338 1,826,643 10/ 1931Anderson 297-338 2,017,300 10/1935 Wiesmau 254-98 2,331,990 10/ 1943McArthur 248-423 2,714,498 8/ 1955 Wufhrich 248-354 2,854,180 9/ 1958Brunckhorst 182-202 2,875,007 2/1959 Fox 248-1885 3,090,466 5/ 1963Wright 182-202 FOREIGN PATENTS 1,071,304 12/ 1959 Germany.

11,484 of 1888 Great Britain. 360,111 11/1931 Great Britain.

FRANK B. SHERRY, Primary Examiner.

F. K. ZUGEL, Examiner.

1. HEIGHT ADJUSTABLE FURNITURE SUPPORT COMPRISING A COLUMN, MEANS FORVERTICALLY SUPPORTING SAID COLUMN ON A HORIZONTAL SURFACE WHEN IN USE, ATUBE TELESCOPICALLY CONNECTED TO ONE END TO SAID COLUMN, A SPRINGMOUNTED ON SAID COLUMN, A SERIES OF BALLS FREELY MOVABLE ANDINDIVIDUALLY ROTATABLE IN SAID TUBE WITH ADJACENT BALLS BEARING AGAINSTONE ANOTHER AND HAVING ONE OF SAID BALLS BEARING AGAINST SAID SPRING,SAID TUBE HAVING A SIDE OPENING, A SUPPORT PIVOTALLY MOUNTED ON SAIDTUBE, AND A BLOCKING MEMBER CARRIED BY SAID SUPPORT FOR BEING INSERTEDAT TIMES THROUGH SAID TUBE SIDE OPENING AND BETWEEN AN ADJACENT PAIR OFSAID BALLS WHEN SAID SUPPORT IS IN ITS LOAD SUPPORTING POSITION.